The word(s) "sinful" appears 13 time(s) in 13 verse(s) in Quran in Mohsin Khan translation.

(1) He [Shaitan (Satan)] commands you only what is evil and Fahsha (sinful), and that you should say against Allah what you know not.

(2) And eat up not one another's property unjustly (in any illegal way e.g. stealing, robbing, deceiving, etc.), nor give bribery to the rulers (judges before presenting your cases) that you may knowingly eat up a part of the property of others sinfully.

(3) And if you are on a journey and cannot find a scribe, then let there be a pledge taken (mortgaging) ; then if one of you entrust the other, let the one who is entrusted discharge his trust (faithfully), and let him be afraid of Allah, his Lord. And conceal not the evidence for he, who hides it, surely his heart is sinful. And Allah is All-Knower of what you do.

(4) And let not the disbelievers think that Our postponing of their punishment is good for them. We postpone the punishment only so that they may increase in sinfulness. And for them is a disgracing torment.

(5) Why do not the rabbis and the religious learned men forbid them from uttering sinful words and from eating illegal things. Evil indeed is that which they have been performing.

(6) O you who believe! When death approaches any of you, and you make a bequest, (then take) the testimony of two just men of your own folk or two others from outside, while you are travelling through the land and death befalls on you. Detain them both after As-Salat (the prayer), (then) if you are in doubt (about their truthfulness), let them both swear by Allah (saying): "We wish not for any worldly gain in this, even though he (the beneficiary) be our near relative. We shall not hide Testimony of Allah, for then indeed we should be of the sinful."

(7) "O Yusuf (Joseph)! Turn away from this! (O woman!) Ask forgiveness for your sin. Verily, you were of the sinful."

(8) They descend on every lying, sinful person.

(9) And whoever brings an evil deed (i.e. Shirk - polytheism, disbelief in the Oneness of Allah and every evil sinful deed), they will be cast down (prone) on their faces in the Fire. (And it will be said to them) "Are you being recompensed anything except what you used to do?"

(10) Woe to every sinful liar